Saw cylinder for cotton extracting machines



May 28,1935. I MITCHEL 2,003,262

SAW CYLINDER FOR COTTON EXTRAGTING MACHINES Filed May 19, 1934 /N VENToeORV/L L E MITCHELL BYWJ Hr-rozusz Patented May 28, 1935 I T F UNITEDSTATES PATENT OFFICE- SAW CYLINDER FOR COTTON EXTRACTIN G MACHINES .i

- rvilleMitchell, Dallas, Tex. Application May 19, 1934, Serial No.726,437

2 Claims. (CI. 19-63) 'I'he'general object of this invention is toprosubstances getting into the machine, as heretovide an all-metalcottonextracting saw cylinder fore mentioned. with the purpose in viewof obviating various 'The invention is illustrated in theaccompanydisadvantages incident to the use of such saw ing drawing, inwhich: 7 cylinders as now generally constructed.. Figure 1 is a"longitudinal sectional view 5 The type of saw cylinder'heretoforegenerally through one end portion of a saw cylinder conused incotton-extracting machinery has either structed according to myinvention; been made up of wooden drumswith saw bands Figure 2 is across-sectional view. taken on the nailed around the periphery of thedrum, or with line 2-2 of Figure 1;

wooden staves extending lengthwise of thedrum Figure 3 is a similar viewtaken on the line 10 and covered with sheet metal, and having the 3--3of Figure 1; saw bands placed around the drum" formed by Figure 4 is aperspective view of one of a pluthe sheet metal, and secured in place bynails rality of disks constituting the main frame or driven through thesheet metal and into the body of the cylinder;

5 wooden staves. Figure'5 is a view of one of the self-threading 5 Suchsaw cylinders have met the requirements screws employed for securing'thesaw bands in of operation with a fair degree of satisfaction, place; andalthough wood capable of holding nails often ."Figure 6 is aview of aportion of one of the splits, especially when the saw bands are nailedtwo end disks of the cylinder illustrating a modio on the second time,or even often'er, which is fication in the manner of providing closedends frequently necessary in replacing saw bands that for the cylinder.s are damaged by hard foreign substances passing Referring now to thedrawing,the numeral i into the extracting machinery with the cotton.indicates a central shaft on which, at equally This, however,constituted a more or less minor spaced intervals, I mount a pluralityof disks, 2,

objection which, toa large extent could be obfor. supporting the outerlongitudinal members 25 viated by selecting the proper character of woodforming the periphery of the drum. Preferably, for constructing thecylinders. these disks are secured to the shaftby having In recentyears, however, a novel method of the metal surrounding the centralaperture drying and conditioning cotton has come into thereinturned-outward to form a supporting extensive commercial use, inpractice of which flange, 3, and the face of the disk and this flange 30currents of air at a high temperature are forced is then'welded to apressed-metal hub, 4, which through the cotton extracting machinery..The in turn is either welded or bolted tothe shaft. presence of thisheated air in the machine causes An important feature of the inventionresides the wood of the saw cylinders to shrink, the nails in theconstruction and means which I employ securing the saw bands of thecylinder become forforming peripheral supports for an outer 35 loose,and the saw bands fall off.. This 0011-? shell or covering, and which atthe same time stitutes a serious disadvantage, and one which providemeans for enabling the saw bands to it has been found practicallyimpossible to avoid be secured on the cylinder. with the use .of anycharacter of :wood. To this end each of the disks 2v is cut on lines 40Furthermore, as the shrinkage; of the wood is extending parallel with adiametrical line of 40 t nif m, h s w ylinde ome'm r r the disk atpreferably four points around the less distorted in shape, causing themto be periphery of the disk,as indicated at 5, in Fige thrown out ofbalance, and producing excessive ure 3, the length of each out beingpreferably vibration in peration. about one-half the length of theradius of the To obviate the above and other difficulties indi k, Themetal is next cut at right angles to 45 cident to the use of wood in theconstruction of th ut 5, a indicated at 6, in a direction to extractorsaw cylinders, I construct the cylinder cross a radius of the disk, thecut 6 being somef sh ttal part a d mpl y a p or what less in length thanthe cut 5. The metal hardened self-threading screws for securing the bunded by the two outs is then bent back at saw bands to the cylinder. Myimproved conright angles to the face of the diskto form lips 50struction to be later described in detail, not only 1, and providingrectangular recesses, 8, extendmakes practicable the use of an all-metalconing, of course, from the cut 6 to the periphery of struction ofextracting cylinder, but facilitates the disk. The disks are so mountedon the shaft changing or replacing any individual saw band that all thecorresponding'recesses 8 of the rewhich might become damaged by reasonof hard spective disks will be in alignment with each 55 other. Mountedwithin each series of recesses 8 is a longitudinal angle-support, 9,which extends the full lengthof the cylinder. Each of these supportscomprises a straight, flat-metal bar, I0, which extends parallel to andin contact with the series of lips I, and which is secured theretoeither by welding, or, as shown, by means of screws, II, passed throughan aperture in each lip and a corresponding aperture in the bar ID. Atits outer end each bar I is bent at right angles on a curved line,corresponding to the curvature of the periphery of the disk,

to form a peripheral support, l2, which extends across and closes theouter, ends of the'line of recesses 8, these supports providing a trueround skeleton support for a sheet metal housing which completes thecylinder.

Three of the peripheral supporting members l2 of each disk are providedwith a line of aper-. tures, l3, spaced a suitable distance apart,whilethefourth supporting member, shown at the top of Figure 3, is providedwith an additional line of apertures, as indicated at M, the aperturesl3 and M of this member being positioned, respectively, on oppositesides of the longitudinal center of the member.

The sheet metal housing, l5, ispreferably made in sections, and, tocomplete the drum, these curved members are first placed around thedisks and supporting members and temporarilyheld in position untilchannelled saw bands, It, are placed around the housing at intervalsthroughout the length of-the cylinder and secured in place. The sawbands are thus secured by means of self-threading screws, I1, driveninto the aperture l3 throughopeningsin the saw bands, and, where theends of the saw bands come together, as shownat the top of Figure3, byan additional line of self-threading screws, Ill.

The openings, I9, in the base or channel of 'the saw bands through whichthe self-threading screws I1 and I8 pass are elongated inshape, asindicated in Figure 1, and are practically the same size as the screwsin the direction transversely of the saw bands, so that if there shouldbe any slight inaccuracy or variation in diameter ofthe drum, someportion of the openings through the saw bands will always come over thecomparatively small apertures through the curved supporting members 13,thus obviating any difficulty in driving the self-threading screws intothe apertures I3 and I4 and holding the saw bands in place.

As shown by Figure 1, as to oneend of the cylinder, each end of thecylinder-may beclosed, that is, the recesses 8 in the end disks covered,by welding on to each end diskv a separate solid disk, 20. p .1

If preferred, and as shown in the modified con-- struction illustratedby Figure 6, the recesses 8 will be omitted from the end disks and lips,2|,

corresponding to the'lips L be welded to the inner face of each disk atfour points around the periphery thereof. A cylinder employing thismodified construction will have the advantage of being somewhat lighterin weight than a cylinder employing the two solid metal disks at theends, as illustrated in Figure 1.

The use of aeroplane, or hard metal selfthreading screws is, to a largeextent a deciding factor in rendering possible the use of an allmetalcotton extracting cylinder. That is to say, when the saw bands have beensecured in place by forcing these screws into the apertures of thecurved supporting members, there is no danger whatever of the saw bandsbecoming loose, or falling off, as these screws will hold fast underalmost any conditions of service. At the same time, they may be removedto enable damaged saw bands tobe replaced with new bands.

I claim:

1. A saw cylinder for cotton extracting machines comprising, in'combination, a shaft, a series of disks secured thereon in spacedrelation, each of said disks being provided with equally spaced,circumferential radial recesses, corresponding recesses of therespective disks aligning, lips projecting, respectively, at rightangles from corresponding sides of said recesses, an angle bar mountedin each aligning series of recesses, each angle bar extending the fulllength of the cylinder and comprising astraight fiat metal membersecured to the lips of its line of recesses and. having an integralcurved supporting member extending across the outer ends of saidrecesses, a sheet metal housing surrounding and supported on said disksand supporting members, and a series of saw bands encircling saidhousing at intervals throughout the length of the cylinder and securedin position by screws passed through apertures in the saw bands andengaged in said supporting members.

2. A saw cylinder for cotton extracting machines comprising, incombination, a shaft, a series of disks secured thereon in spacedrelation, each of said disks being provided with equally? spaced,circumferential, radial recesses, corresponding recesses of therespective disks aligning, and the metal at one side of each recessbeing bent'outward at right angles to form a lip, an angle-bar mountedin each aligning series of recesses, each angle bar extending the fulllength of the cylinder, and comprising a. straight, flat metal membersecured to the lips of a line of recesses and having an integral curvedsupporting member extending across the outer ends of the recesses, asheet metal housing surrounding and supported on said disks andsupporting members, and a series of saw bands encircling said housingat. intervals throughout the length of the cylinder and secured inposition by screws passed through apertures in the saw bands and engagedin said supporting members.

ORVILLE MITCHELL.

